package com.lyy.common.websocket;

import com.sun.jersey.client.impl.CopyOnWriteHashMap;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

@Slf4j
@Component
@ServerEndpoint(value = "/websocket/{param}")
public class WebSocket {

    // 静态变量，用来记录当前在线连接数。应该把它设计成线程安全的。
    private static int onlineCount = 0;

    // concurrent包的线程安全Set，用来存放每个客户端对应的MyWebSocket对象。
    private static final CopyOnWriteHashMap<String, Map<String, WebSocket>> WEB_SOCKET_SET = new CopyOnWriteHashMap<String, Map<String, WebSocket>>();

    // 与某个客户端的连接会话，需要通过它来给客户端发送数据
    private Session session;

    /**
     * 连接建立成功调用的方法
     */
    @OnOpen
    public void onOpen(Session session, @PathParam(value = "param") String param) {
        this.session = session;
        addOnlineCount(); // 在线数加1
        log.info("有新连接加入！" + param + "当前在线人数为" + getOnlineCount());
        String sessionId = session.getId();
        Map<String, WebSocket> map = null;
        if (WEB_SOCKET_SET.containsKey(param)) {
            map = WEB_SOCKET_SET.get(param);
        } else {
            map = new HashMap<String, WebSocket>();
        }
        map.put(sessionId, this);
        WEB_SOCKET_SET.put(param, map); // 加入set中
        try {
            sendMessage("连接成功");
        } catch (IOException e) {
            log.error("IO异常");
        }
    }

    /**
     * 连接关闭调用的方法
     */
    @OnClose
    public void onClose(@PathParam(value = "param") String param) {
        if (WEB_SOCKET_SET.containsKey(param)) {
            Map<String, WebSocket> map = WEB_SOCKET_SET.get(param);
            String sessionId = session.getId();
            if (map.containsKey(sessionId)) {
                map.remove(sessionId);    //从set中删除
                subOnlineCount();        //在线数减1
                if (map.size() <= 0) {
                    WEB_SOCKET_SET.remove(param);    //从set中删除
                }
                log.info("有一连接关闭！当前在线人数为" + getOnlineCount());
            }
        }
    }

    /**
     * 收到客户端消息后调用的方法
     *
     * @param message 客户端发送过来的消息
     */
    @OnMessage
    public void onMessage(String message, Session session, @PathParam(value = "param") String param) {
        log.info("来自客户端" + param + "的消息:" + message);
        if (WEB_SOCKET_SET.containsKey(param)) {
            Map<String, WebSocket> map = WEB_SOCKET_SET.get(param);
            String sessionId = session.getId();
            if (map.containsKey(sessionId)) {
                map.remove(sessionId); // 从set中删除
                subOnlineCount(); // 在线数减1
                if (map.size() <= 0) {
                    WEB_SOCKET_SET.remove(param); // 从set中删除
                }
                log.info("有一连接关闭！当前在线人数为" + getOnlineCount());
            }
        }
    }

    /**
     * 发生错误时调用
     */
    @OnError
    public void onError(Session session, Throwable error) {
        log.error("发生错误", error);
        error.printStackTrace();
    }

    public void sendMessage(String message) throws IOException {
        this.session.getBasicRemote().sendText(message);
        //this.session.getAsyncRemote().sendText(message);
    }

    public void remove(String param, String sessionId) {
        if (WEB_SOCKET_SET.containsKey(param)) {
            Map<String, WebSocket> map = WEB_SOCKET_SET.get(param);
            if (map.containsKey(sessionId)) {
                map.remove(sessionId);    //从set中删除
                subOnlineCount();        //在线数减1
                if (map.size() <= 0) {
                    WEB_SOCKET_SET.remove(param);    //从set中删除
                }
                log.info("有一连接关闭！当前在线人数为" + getOnlineCount());
            }
        }
    }

    /**
     * 群发自定义消息
     */
    public static void sendInfo(String message) throws IOException {
        for (Map<String, WebSocket> item : WEB_SOCKET_SET.values()) {
            for (WebSocket item2 : item.values()) {
                try {
                    item2.sendMessage(message);
                } catch (IOException e) {
                    log.error("webSocket推送失败", e);
                }
            }
        }
    }

    public static synchronized int getOnlineCount() {
        return onlineCount;
    }

    public static synchronized void addOnlineCount() {
        WebSocket.onlineCount++;
    }

    public static synchronized void subOnlineCount() {
        WebSocket.onlineCount--;
    }

    public static synchronized Map<String, WebSocket> getWebSockets(String param) {
        return WEB_SOCKET_SET.get(param);
    }

}